In present day and future portable computing systems (platforms) and portable communications systems, battery design plays an important role for optimizing performance as well as in ergonomic issues such as portability. In some designs, for example, battery configurations may involve only two battery cells arranged in series, which entails a lower input voltage for the platform to be powered by the battery.
The lower input voltage provided to a given computing/communications platform by a battery such as a two battery cell configuration places restrictions on the central processing unit (CPU) device performance in a portable device when the portable device is powered by the battery. For example, if a CPU is operating in an enhanced operation mode, such as a so called “Dynamic Turbo” mode, and battery cells discharge, the system voltage may droop below a minimum voltage required by the platform power delivery.
In one example of operation of known computing platforms, one or more 5V voltage regulators (VRs) may be designed so that proper operation requires a minimum input voltage to the VR of between 5.2 V and 6 V. During operation, the individual or collective activity of one or more devices in a mobile computing/communications platform may cause a large power spike, including for example, the action of a processor such as a CPU when operating in a Dynamic Turbo mode. Assuming that a total resistance from the battery cells (including the internal cell resistance) to the input of a 5V regulator is equal to 100 mOhm, and a minimum input 5V VR voltage of 5.6V, the battery cell voltage of 3.5V—above the traditional cut-off voltage of the cells. To account for such circumstances, a conservative system design would require the mobile computing system to drastically lower the CPU maximum current (Imax) and performance when the battery cells are a voltage level of 3.5V—which may severely restrict usage of the mobile computing platform for end-users. Such system design takes into account maximum projected power consumption, which may take place in real operation of the mobile computing platform only under rare circumstances if at all. Accordingly, system performance of a mobile computing system powered by a lower voltage battery design may be sacrificed in order to accommodate unlikely operation scenarios.
It is with respect to these and other considerations that the present improvements have been needed.